Integration of copper into an IC manufacturing process can be implemented by using dual damascene processing, in which Chemical Mechanical Polishing (CMP) has been used to remove the overburden material and planarize the wafer surface.
CMP is the best approach for copper interconnects layers to obtain global planarization, while the slurry is the most important and critical factor in the polishing process. The slurry for copper CMP is composed of abrasive particles and chemicals such as inorganic or organic acids, corrosion inhibitors, oxidizers and complexing agents. The inorganic particles used such as abrasives have high removal rate (RR), but they are hard and they can create many scratches and damages not only on copper but also on the silica film surface.